In a method well known in the art for managing program operation data, such as that disclosed in Japanese Patent Application Publication No. H08-249215, when a fault or other abnormality occurs during program operations for controlling devices, the device used when the abnormality occurred is detected and data required for investigating the cause of the abnormality occurring in the detected device is stored and provided to the user. With a data processor, data processing program, and data processing system employing this method of managing program operation data, data related to the operational environments of programs controlling specific devices is collected and stored in a program data management table of a shared memory. Accordingly, if an abnormality occurs when a program is used to control a specific device, the program data management table can be referenced to quickly retrieve data in order to reduce the time required for investigating the cause of the abnormality.